[alsa-devel] [V2 PATCH] ALSA: hda - Enable mute/mic-mute LEDs for more Thinkpads with Conexant codec

[Takashi Iwai]

At Sat, 27 Jun 2015 12:50:44 -0300,
Henrique de Moraes Holschuh wrote:
> 
> On Sat, 27 Jun 2015, Jan Kiszka wrote:
> > > Please explain _in detail_ what you mean with "changing a power button to a
> > > reset button by acessing the SSMS ACPI method in a X121e".
> > > 
> > > Are we trigering a bug somewhere that crashes the x121e and causes it to
> > > reboot?
> > 
> > Well, there aren't much details to describe in this case: When this
> > patch is applied and I press the power button, the device performs a
> > hard reset. It doesn't reveal if the kernel crashes catastrophically,
> > causing a triple fault or so, or if the firmware decides to reset the
> > platform. Reverting the patch or preventing its effect via a quirk
> > filter like I posted [1] makes the issue go away.
> 
> Ok, so we crashing the firmware, and on a box that is not likely to get
> further updates.  Well, this is a pretty clear case: blacklist.
> 
> Since calling SSMS in the X121e is unsafe, it needs to be blacklisted in
> thinkpad-acpi.  I will need dmidecode output for that (please XXX-out UUIDs
> and serial numbers in the dmidecode output before you send it to me, but do
> keep model numbers intact).
> 
> We can also have a blacklist in ALSA to avoid the whole symbol_request() for
> something that will have to fail, of course.  I leave that for the ALSA
> maintainers to decide.

IMO, it's simpler to just leave the decision in thinkpad_acpi.

> That said, you blacklisted in ALSA by full codec->subsystem_id.  Which
> thinkpads have the 0x17aa21ec subsystem ID on the codec?  Just the x121e?

It's not guaranteed, but Lenovo doesn't share the same PCI SSID for
multiple models, AFAIK.


thanks,

Takashi